Audiences watching Martin McDonagh’s crime film Three Billboards Outside Ebbing, Missouriwill be forgiven for thinking, at a certain point, that they know how it will end. (Spoilers ahead!) In the film, Mildred Hayes (Frances McDormand) rents three billboards in her small Missouri town to call out the police department for leaving her daughter Angela’s rape and murder unsolved. Sam Rockwell plays Dixon, an aggressive and largely incompetent police officer who takes Mildred’s vendetta personally.

The two characters spend the film butting heads, with consequences that are often unexpectedly violent. Then Dixon overhears a strange man bragging about a crime that sounds much like Angela’s murder. For a moment, it looks like the killer might finally be brought to justice after all…

But writer-director McDonagh doesn’t let the audience off the hook that easily. “It was about not wrapping up the story with a bow, not finding the solution and that person getting his comeuppance and all of that,” McDonagh told Yahoo Entertainment. “Because the story is more about change than it is about solutions.” The stranger, Dixon learns, has a rock-hard alibi for the night of Angela’s death. He must therefore have been bragging about a different rape and murder. Dixon (who by this point in the story has been fired from the police department) comes to Mildred with an idea: Since her daughter’s killer hasn’t been found, they can take revenge on this killer instead. The film ends with the two characters driving away, having their first-ever friendly conversation, and wondering aloud whether they’ll actually go through with killing the stranger.

During interviews with Yahoo Entertainment about Three Billboards, McDonagh and Rockwell each offered a different take on the film’s ambiguous ending. Rockwell admitted he’d gone back and forth in his own mind about where Mildred and Dixon were headed. “At first I thought they were going to go kill people, and then I thought maybe not,” said Rockwell.

Sam Rockwell as Dixon, with Frances McDormand in a scene from the film Three Billboards Outside Ebbing, Missouri (Image: Merrick Morton/ 2017 Twentieth Century Fox Film Corporation)

After discussions with co-star McDormand, Rockwell came to the conclusion that Mildred and Dixon “probably just go to a bar to get some liquid courage to go kill the guy, and then they just decide not to. And they just get drunk and make out.”

Naturally, McDonagh takes a longer view. “The conversation they have in the car is the most important one in the film, because it’s about how much they’ve changed from the start of the story,” he said. “The fact that they could even sit in a car and have a conversation is momentous, and to have complete doubt about violence and where they’re at with it.” And, he noted, “It’s almost the only time she smiles in the film, which is a big change.”

However, McDonagh pointed out that there is one variable that could send Mildred back over the edge: She has already met the stranger. In a disturbing scene earlier in the film, the man visits the shop where Mildred works, and his casually menacing behavior leads Mildred to wonder if he could be her daughter’s killer. “Mildred doesn’t know it’s going to be that guy from the shop when she meets him,” said McDonagh. “So even though she’s probably more reticent than Sam is about doing something, I wonder what happens when she sees who he is.”

It’s a question McDonagh very deliberately left unanswered. (Though McDonagh has joked that he’ll explore it in the sequel, he told Yahoo Entertainment that he is utterly opposed to making sequels.) To him, the ending is about the journey: “They’re still driving ahead. But they’re driving ahead with more doubt and more humanity than they began with.”